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1.
PeerJ ; 7: e6789, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024778

RESUMO

The aim of this work was to test and analyse the bioeffects of Prunus spinosa L. (Rosacaee) fruit ethanol extract on Trichoplax adhaerens Schulze, 1883 (Placozoa) laboratory cultures which-for the first time-were employed as in vivo biological model to assess the bioactivity of a natural extract. The ethanol extract of P. spinosa was administrated during a 46 day experimental period; ultrastructural (by optical, confocal, TEM and SEM microscopy) and morphometric analyses indicated that treated Trichoplax adhaerens showed significant differences in viability, reproductive modalities, body shape and colour with respect to the control group. Finally, P. spinosa bioactive compounds seem to exert profound protective effects on T. adhaerens reproduction and phenotype. Our results may support additional investigations related to other bioactive compounds properties useful for nutraceutical preparations to be used as food supplements.

2.
Sci Rep ; 9(1): 2067, 2019 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-30765851

RESUMO

The order Macrodasyida (Gastrotricha) includes over 350 marine species, and only 3 freshwater species (Marinellina flagellata, Redudasys fornerise, R. neotemperatus). Herein we describe a new freshwater species of Macrodasyida, Redudasys brasiliensis sp. nov., from Brazil through an integrative taxonomic approach. The external morphology and internal anatomy were investigated using differential interference contrast microscopy, confocal microscopy, scanning and transmission electron microscopy. The systematization of the new taxon was inferred by nuclear (18S and 28S) and mitochondrial (COI) genes, and its intra-order relationships were assessed using data from most of available macrodasyids. Phylogenetic analyses yielded congruent trees, in which the new taxon is nested within the family Redudasyidae, but it was genetically distinct from the other species of the genus Redudasys. The new species shares the gross morphology and reproductive traits with other Redudasyidae and the presence of only 1 anterior adhesive tube per side with Redudasys neotemperatus, but it has a specific pattern of ventral ciliation and muscle organization. Results support the hypothesis that dispersion into fresh water habitats by Macrodasyida and Chaetonotida taxa occurred independently and that within Macrodasyida a single lineage invaded the freshwater environment only once. Furthermore, the Neotropical region seems to be peculiar for the evolution of the freshwater macrodasyid clade.


Assuntos
Helmintos/classificação , Helmintos/genética , Animais , Brasil , Ecossistema , Evolução Molecular , Água Doce , Microscopia Eletrônica de Transmissão/métodos , Microscopia de Interferência/métodos , Mitocôndrias/genética , Filogenia , RNA Ribossômico 18S/genética
3.
Environ Toxicol Chem ; 37(9): 2439-2447, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29920754

RESUMO

Lead (Pb) is regarded as a highly toxic element that poses a serious threat to biota. A mesocosm experiment was performed to assess the influence of Pb on meiofaunal (metazoans within 45-500 µm) and benthic foraminiferal (protozoan) communities. To this end, sediments bearing such communities were incubated in mesocosms, exposed to different levels of Pb in seawater, and monitored for up to 8 wk. Concentrations of Pb <1 ppm in water did not promote a significant increase of this metal in sediments. Relatively high concentrations of Pb seemed to affect meiofaunal and benthic foraminiferal communities by reducing their richness or diversity, and the abundance of the most sensitive taxa. The mesocosm approach can be considered an effective method to document the responses of meiofaunal and benthic foraminiferal communities to various kinds and concentrations of pollutants over time. This approach allows the evaluation of dose-response relationships, validates the outcomes of field studies, and possibly confirms the sediment quality guidelines and thresholds. Environ Toxicol Chem 2018;37:2439-2447. © 2018 SETAC.


Assuntos
Monitoramento Ambiental/métodos , Foraminíferos/efeitos dos fármacos , Sedimentos Geológicos/química , Chumbo/toxicidade , Água do Mar/química , Poluentes Químicos da Água/toxicidade , Biodiversidade , Relação Dose-Resposta a Droga , Chumbo/análise , Mar Mediterrâneo , Modelos Teóricos , Poluentes Químicos da Água/análise
4.
Mar Environ Res ; 139: 19-26, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29753494

RESUMO

Marine biologists have progressively increased their consciousness of the importance of meiofauna for the benthic domain in both temperate and tropical regions. After the 1998 bleaching, Maldivian reefs (Indian Ocean) have been regarded as a vulnerable ecosystem that must be carefully monitored. Accordingly, an extensive investigation of meiofaunal distribution in the reef slopes of the Maldivian archipelago has been carried out, taking into account geographical position, type of habitat (inner vs. outer slope), inclination and depth gradient. Twenty-four taxa revealed the highest meiofaunal richness ever found in Maldivian reefs. Interestingly, Thermosbenacea and Syncarida were identified, which are two taxa that have only recently been documented in the marine ecosystem. Chaetognatha were also present, which is a group that was only considered to be planktonic until 2000, when they were also discovered in the benthos. The type of habitat, affected by different hydrodynamic conditions, was the main factor influencing the meiofaunal community's structure and diversity. In detail, the outer reefs were characterized by the highest level of diversity, confirming previous observations on the rate of coral reef growth and vitality and underlining the greater vulnerability of the inner slopes. In contrast, depth only significantly affected the community structure, but not its density or diversity. Accordingly, community structure seems to be more sensitive than abundance and diversity indices when it comes to detecting depth gradients. The 10° inclination of the inner slopes revealed the most different community structure and the greatest dominance of nematodes, leading to the lowest diversity levels.


Assuntos
Organismos Aquáticos/classificação , Biodiversidade , Recifes de Corais , Monitoramento Ambiental , Invertebrados/classificação , Animais , Antozoários , Organismos Aquáticos/crescimento & desenvolvimento , Ecossistema , Oceano Índico , Invertebrados/crescimento & desenvolvimento , Nematoides
5.
New Microbiol ; 41(1): 80-82, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29112768

RESUMO

We describe two cases of Zika virus infection involving an Italian patient returning from the Dominican Republic and his wife, who remained in Italy and had not travelled to Zika virus endemic areas in the previous months. The infection was transmitted through unprotected sexual intercourse after the man's return to Italy.


Assuntos
Doenças Virais Sexualmente Transmissíveis/epidemiologia , Infecção por Zika virus/transmissão , Zika virus/imunologia , Anticorpos Antivirais/sangue , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/virologia
6.
Zootaxa ; 4258(4): 375-387, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28609913

RESUMO

Five species of suctorian ciliates belonging to four different genera attached to meiofaunal organisms of Maldivian archipelago (Suvadiva Atoll) were documented. Three rare species (Acineta sp., Thecacineta urceolata Liao & Dovgal, 2015 and Limnoricus ceter Jankowski, 1981) and one common suctorian ciliate Thecacineta calix (Schröder, 1907) are re-described from nematodes (Croconema cinctum Cobb, 1920, Desmodorella tenuispiculum Allgén, 1928 and Desmodora sp.) and harpacticoid copepod basibionts. In addition, Trophogemma colantonii n. sp. colonizing the abdomen and legs of the harpacticoid copepod Stenhelia sp. is described. The new species differs from the relative species for the less flattened cell body, the absence of both lateral bundles of tentacles and separate lateral tentacles as well as for the presence of longitudinal ribs along the cuticle. The data obtained in this survey give not only new important information on the taxonomy and distribution of Suctorea, but also new insights on their relationship with meiofaunal organisms in one of the most diverse and productive marine micro-habitat of carbonate sediments.


Assuntos
Cilióforos , Adenofórios , Animais , Copépodes , Ecossistema , Nematoides
7.
Subj. procesos cogn ; 21(1): 219-239, 2017.
Artigo em Espanhol | LILACS | ID: biblio-875358

RESUMO

El presente trabajo se propone realizar un estudio preliminar sobre el Test de los Cuentos de Hadas (Fairy Tale Test) de Carina Coulacoglou, dar a conocer las primeras experiencias de la investigación transcultural iniciada en Argentina con el objetivo de evaluar su aplicabilidad en nuestra población, y comparar su status clínico y científico con otras técnicas temáticas incorporadas al psicodiagnóstico infantil. El principal aporte del TCH se centra en enriquecer y profundizar la comprensión de la personalidad infantil, en niños y niñas de 6 a 12 años de edad, utilizando láminas que presentan personajes y escenas de cuentos tradicionales como los de Caperucita Roja y Blancanieves. La cuidadosa operacionalización de las variables y los aspectos psicométricos del instrumento lo diferencian de otras técnicas proyectivas de uso común en el psicodiagnóstico infantil. Su encuadre lúdico y el atractivo de las láminas promueven una interacción continua entre el niño y el psicólogo sosteniendo el interés y la motivación del niño. El TCH ha demostrado eficacia en estudios transculturales, en investigaciones clínicas y del área educacional.(AU)


The present work intends to carry out a preliminary study on Carina Coulacoglou's Fairy Tale Test, to expose the first experiences of the cross­cultural investigation initiated in Argentina in order to assess its applicability in our population and compare their clinical and scientific status with other theme techniques incorporated to children's psychodiagnosis. The main contribution of the FTT is the enhancement and elaboration of the understanding of children personality, in boys and girls 6 to 12 years old, using pictures featuring characters and scenes of traditional tale, such as little Red Riding Hood and Snow White. The careful operationalization of variables as well as the psychometric aspects of the instrument differ from other projective techniques commonly used in children psychodiagnosis. Its ludic frame and the appealing pictures promote interaction on a continuous basis between the child and the psychologist, maintaining the interest and motivation of the child throughout. The FTT has shown efficacy in transcultural studies, both in clinical and educational research. (AU)


Assuntos
Humanos , Criança , Técnicas Projetivas , Psicologia
8.
Biodivers Data J ; (3): e5800, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26379467

RESUMO

Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Gastrotricha are a meiobenthic phylum composed of 813 species known so far (2 orders, 17 families) of free-living microinvertebrates commonly present and actively moving on and into sediments of aquatic ecosystems, 339 of which live in fresh and brackish waters. The Fauna Europaea database includes 214 species of Chaetonotida (4 families) plus a single species of Macrodasyida incertae sedis. This paper deals with the 224 European freshwater species known so far, 9 of which, all of Chaetonotida, have been described subsequently and will be included in the next database version. Basic information on their biology and ecology are summarized, and a list of selected, main references is given. As a general conclusion the gastrotrich fauna from Europe is the best known compared with that of other continents, but shows some important gaps of knowledge in Eastern and Southern regions.

9.
PLoS One ; 7(5): e36881, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22649502

RESUMO

The number of described species on the planet is about 1.9 million, with ca. 17,000 new species described annually, mostly from the tropics. However, taxonomy is usually described as a science in crisis, lacking manpower and funding, a politically acknowledged problem known as the Taxonomic Impediment. Using data from the Fauna Europaea database and the Zoological Record, we show that contrary to general belief, developed and heavily-studied parts of the world are important reservoirs of unknown species. In Europe, new species of multicellular terrestrial and freshwater animals are being discovered and named at an unprecedented rate: since the 1950s, more than 770 new species are on average described each year from Europe, which add to the 125,000 terrestrial and freshwater multicellular species already known in this region. There is no sign of having reached a plateau that would allow for the assessment of the magnitude of European biodiversity. More remarkably, over 60% of these new species are described by non-professional taxonomists. Amateurs are recognized as an essential part of the workforce in ecology and astronomy, but the magnitude of non-professional taxonomist contributions to alpha-taxonomy has not been fully realized until now. Our results stress the importance of developing a system that better supports and guides this formidable workforce, as we seek to overcome the Taxonomic Impediment and speed up the process of describing the planetary biodiversity before it is too late.


Assuntos
Biodiversidade , Classificação/métodos , Pesquisa , Animais , Europa (Continente) , Especificidade da Espécie
10.
PLoS One ; 6(5): e19639, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21625556

RESUMO

Unraveling animal life cycles and embryonic development is basic to understanding animal biology and often sheds light on phylogenetic relationships. A key group for understanding the evolution of the Metazoa is the early branching phylum Placozoa, which has attracted rapidly increasing attention. Despite over a hundred years of placozoan research the life cycle of this enigmatic phylum remains unknown. Placozoa are a unique model system for which the nuclear genome was published before the basic biology (i.e. life cycle and development) has been unraveled. Four organismal studies have reported the development of oocytes and one genetic study has nourished the hypothesis of sexual reproduction in natural populations at least in the past. Here we report new observations on sexual reproduction and embryonic development in the Placozoa and support the hypothesis of current sexual reproduction. The regular observation of oocytes and expressed sperm markers provide support that placozoans reproduce sexually in the field. Using whole genome and EST sequences and additional cDNA cloning we identified five conserved sperm markers, characteristic for different stages in spermatogenesis. We also report details on the embryonic development up to a 128-cell stage and new ultrastructural features occurring during early development. These results suggest that sperm and oocyte generation and maturation occur in different placozoans and that clonal lineages reproduce bisexually in addition to the standard mode of vegetative reproduction. The sum of observations is best congruent with the hypothesis of a simple life cycle with an alternation of reproductive modes between bisexual and vegetative reproduction.


Assuntos
Linhagem da Célula , Embrião não Mamífero/citologia , Evolução Molecular , Oócitos/citologia , Placozoa/crescimento & desenvolvimento , Placozoa/metabolismo , Reprodução/fisiologia , Animais , Placozoa/embriologia , Proteínas de Plasma Seminal/metabolismo , Espermatogênese
11.
J Morphol ; 272(3): 371-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21246596

RESUMO

The morphology and ultrastructure of 10 clonal placozoan lineages were studied. We scored several morphological characters at a cellular and intracellular level and identified a number of morphological differences among clones. Some differences appear clone specific and allow recognizing five distinct lineages based on morphological criteria only. These data will be crucial for a yet to be established placozoan systematics. Furthermore, we here describe three new diagnostic morphological characters for Placozoa: a new structure in the upper epithelium, called "concave disc," two distinct subpopulations of fiber cells, and especially small cells in the body margin. Besides the fiber cells appear to be arranged in several layers forming a complex, three-dimensional net not previously described. We also describe the marginal cells as the formerly suggested potential stem-cell type. The basic morphology is revised.


Assuntos
Placozoa/anatomia & histologia , Placozoa/ultraestrutura , Animais , Epitélio/anatomia & histologia , Epitélio/ultraestrutura , Microscopia Eletrônica , Placozoa/classificação
12.
Environ Monit Assess ; 180(1-4): 325-44, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21120690

RESUMO

Many coastal areas have served as repositories of different anthropogenic and naturally induced organic material and nutrients. The major sources thereof are riverine inputs which strongly influence the spatial and temporal distribution of benthic communities. In this study, the benthic foraminiferal, meiofaunal, and macrofaunal colonies in front of three rivers in a poorly known, but environmentally valuable, area of the Central Adriatic Sea have been examined concurrently. The physico-chemical parameters of bottom water and sediment characteristics were determined in order to characterize both the sediment-water interface and the benthic environments. Although changes in the biota are neither univocal nor unidirectional, a moderate influence of riverine input on the different communities' components can be inferred. The most affected taxa are foraminifera and copepods and, to a lesser extent, meiofaunal polychaetes and platyhelminthes. These results are also tested by the ABC curves, which reveal that the macrofaunal communities closest to the river mouths are moderately disturbed. This integrated investigation documents, for the first time, how benthic communities can be used as an early warning indicator with which to monitor the health quality of a coastal ecosystem.


Assuntos
Organismos Aquáticos/classificação , Biodiversidade , Ecossistema , Invertebrados/classificação , Animais , Organismos Aquáticos/crescimento & desenvolvimento , Monitoramento Ambiental , Foraminíferos/classificação , Foraminíferos/crescimento & desenvolvimento , Invertebrados/crescimento & desenvolvimento , Itália , Mar Mediterrâneo , Platelmintos/classificação , Platelmintos/crescimento & desenvolvimento , Poliquetos/classificação , Poliquetos/crescimento & desenvolvimento , Água do Mar/química , Estresse Fisiológico , Poluentes da Água/análise
13.
Zookeys ; (60): 1-12, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21594197

RESUMO

Current knowledge of freshwater gastrotrich fauna from Brazil is underestimated as only two studies are available. The present communication is a taxonomic account of the first-ever survey of freshwater Gastrotricha in Minas Gerais State. Samplings were carried out yielding six species of three Chaetonotidae genera: Aspidiophorus cf. pleustonicus, Ichthydium cf. chaetiferum, Chaetonotus acanthocephalus, Chaetonotus heideri, Chaetonotus cf. succinctus, Chaetonotus sp., and also an undescribed species belonging to the genus Redudasys (incertae sedis): this is the first finding of specimens of Redudasys outside of original type locality. These preliminary observations suggest that the knowledge of the biodiversity of Gastrotricha in the Minas Gerais State, as well as in the whole Brazil, will certainly increase as further investigations are undertaken, and that freshwater Macrodasyida may be more common than previously thought.

14.
Rev. Fac. Odontol. (B.Aires) ; 24(56/57): 40-42, 2009. ilus
Artigo em Espanhol | LILACS | ID: lil-585577

RESUMO

La disostosis cleidocraneal (DCC) es una alteración general infrecuente. Afecta huesos largos, especialmente clavícula y en el área maxilofacial observamos anomalías de número, de erupción, prognatismo y ensanchamiento del arco cigomático. Surge de la mutación del gen CBFA 1/Run X2 ubicado en el cromosoma 6p21 considerado el gen maestro en la formación de huesos y dientes. El propósito de este trabajo fue presentar un caso clínico estudiado radiográficamente y apoyado en la revisión bibliográfica de dicha patología. Esta revisión es coincidente en sus aspectos tanto dentarios como esqueletales de nuestro caso.


Assuntos
Humanos , Feminino , Idoso de 80 Anos ou mais , Anormalidades Maxilomandibulares/etiologia , Displasia Cleidocraniana/diagnóstico , Displasia Cleidocraniana/patologia , Displasia Cleidocraniana , Diagnóstico Diferencial , Prognatismo/etiologia , Radiografia Panorâmica/métodos
15.
Rev. Fac. Odontol. (B.Aires) ; 24(56/57): 40-42, 2009. ilus
Artigo em Espanhol | BINACIS | ID: bin-124102

RESUMO

La disostosis cleidocraneal (DCC) es una alteración general infrecuente. Afecta huesos largos, especialmente clavícula y en el área maxilofacial observamos anomalías de número, de erupción, prognatismo y ensanchamiento del arco cigomático. Surge de la mutación del gen CBFA 1/Run X2 ubicado en el cromosoma 6p21 considerado el gen maestro en la formación de huesos y dientes. El propósito de este trabajo fue presentar un caso clínico estudiado radiográficamente y apoyado en la revisión bibliográfica de dicha patología. Esta revisión es coincidente en sus aspectos tanto dentarios como esqueletales de nuestro caso.(AU)


Assuntos
Humanos , Feminino , Idoso de 80 Anos ou mais , Displasia Cleidocraniana/diagnóstico , Displasia Cleidocraniana/patologia , Displasia Cleidocraniana/diagnóstico por imagem , Anormalidades Maxilomandibulares/etiologia , Radiografia Panorâmica/métodos , Prognatismo/etiologia , Diagnóstico Diferencial
16.
Water Environ Res ; 80(4): 346-54, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18536486

RESUMO

The activated sludge process is performed by a variable and mixed community of microorganisms in an aerobic aquatic environment, in which bacteria constitute the majority and represent the main microorganisms responsible for the degradation process in a plant. In this work, we monitored bacterial charge in different wastewater treatment plants by flow cytometry, also evaluating chlorination effects on bacterial viability, both by flow cytometry and traditional plate counts. Maximum values of bacterial charge were registered in the aeration tank of all plants monitored. Cell viability did not show significant differences (p > 0.05) in samples collected in "before chlorination" and "wastewater effluent" treatment steps; this suggests that the chlorination was not able to decrease total viable bacterial charge. In this work, we discuss the need to improve microbiological analyses, both in terms of measuring other potential pathogens and of using new methodological approaches in the traditional evaluation of the microbiological quality of effluents.


Assuntos
Citometria de Fluxo , Halogenação , Viabilidade Microbiana , Esgotos/microbiologia , Purificação da Água/normas
17.
Cytometry B Clin Cytom ; 70(3): 149-53, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16572416

RESUMO

BACKGROUND: In a wastewater treatment plant, the degradation process is performed by a variable and mixed community of microorganisms in an aerobic aquatic environment. The activated-sludge process is based on the formation of strong microbial flocs where many bacteria are attached to sludge flocs. METHODS: Cytometric analysis requires an homogeneous cell suspension and so detachment of bacteria from flocs is required. In this study, sonication and homogenization were compared to find the most adequate pretreatment method for bacterial cytometric analysis in activated sludge samples. Bacterial viability was tested with a nucleic acid double-staining (NADS) protocol (Barbesti et al., Cytometry 2000;40:214-218) and on flow cytometry. RESULTS: Each method showed a good efficiency in terms of bacterial detachment; thus finally, the choice of which could be the best treatment method was based on both viability results and analysis rapidity. On the basis of the degree of cell detachment and viability, the maximum value was obtained by sonication (2 x 45''). CONCLUSIONS: The use of flow cytometry in conjunction with fluorescent dyes and an adequate pretreatment represents a useful method to rapidly detect and enumerate bacteria in activated sludge samples.


Assuntos
Bactérias/crescimento & desenvolvimento , Citometria de Fluxo/métodos , Técnicas Microbiológicas/métodos , Esgotos/microbiologia , Bactérias/química , Aderência Bacteriana , Contagem de Colônia Microbiana , Corantes Fluorescentes/química , Compostos Orgânicos/química , Propídio/química , Sonicação , Coloração e Rotulagem/métodos
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